diff --git a/.github/workflows/main.yaml b/.github/workflows/main.yaml
index 4f2a5ec2c..5026bc3ee 100644
--- a/.github/workflows/main.yaml
+++ b/.github/workflows/main.yaml
@@ -42,7 +42,7 @@ jobs:
       - run: poetry build
         env:
           POETRY_DYNAMIC_VERSIONING_BYPASS: 0.0.0
-      - run: python3 -m pip install --user --force-reinstall dist/c2cciutils-0.0.0-py3-none-any.whl[checks,publish]
+      - run: python3 -m pip install --user --force-reinstall dist/c2cciutils-0.0.0-py3-none-any.whl[checks,publish] 'ruamel.yaml<0.18.0'
       - run: rm -rf dist build
 
       - name: Checks